Comparison of computerized tomography and radionuclide imaging in "stroke".

Abstract

SUMMARY Forty patients were studied by computerized tomography and by radionuclide brain imaging. The final diagnosis was infarction in 29 patients, intracerebral hematoma in seven, acute SAH in one, and old cerebrovascular accidents in three. CT was far superior to RN in detecting intracerebral hematomas and distinguishing them from cerebral infarction. The results of CT and RN tests were comparable regarding the percentage of abnormalities. However, the results in the same patients were not identical in 55% of the cases, indicating a complementary role for the two tests. There was no relationship between the frequency of abnormalities on CT and the time lapse after the onset of cerebral infarction. RN uptake was not seen in patients with old cerebrovascular accidents.SINCE THE INTRODUCTION of computerized tomography (CT) as a noninvasive technique for brain imaging, several reports have discussed its usefulness in patients with stroke. The purpose of this communication is to compare CT and radionuclide brain scanning in patients with cerebrovascular disease. MethodsThere were 40 patients with a final diagnosis of cerebrovascular accident. Each patient was examined by CT and radionuclide (RN) brain imaging. There were 29 cases of recent infarction (28 in the cerebral hemisphere and one in the cerebellum), seven cases of intracerebral hemorrhage, and one with subarachnoid hemorrhage (SAH). The diagnosis of cerebral infarction was made on clinical grounds. The diagnosis of intracerebral hematoma was confirmed by surgery in three cases and by autopsy in two. There were two cases in this series in which the diagnosis of a hematoma was based on the CT scan. The interval between the onset of symptoms and the diagnostic imaging in this group of patients is shown in table 1. The time lapse between CT and RN brain imaging was less than one week in the same patient, with a mean of 1.8 days. As shown in table 1, CT was done in the first two days in 15 patients, between two and seven days after the onset in 13 patients, between seven and 21 days in six patients, and more than 21 days after the onset in six patients. RN studies were done in the first two days in 18 patients, between two and seven days after the episode in 13 patients, between seven and 21 days in four patients, and more than 21 days after the episode in five patients. Three patients admitted for evaluation of late sequelae of a cerebrovascular accident that had occurred one year earlier are included in the last column of table 1. In this study there was a slight inadvertent selection of patients resulting in a slight artificial bias in the results. During the greater part of the period covered in this study there was a single CT unit in operation at our institute. As a result of the inevitable waiting list, some patients with a negative RN study were not studied by CT. It is quite possible, therefore, that a group of patients with negative isotope studies and positive CT was inadvertently omitted from the study. This will be discussed later.CT scans were pe...

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Cerebral Infarctions with Negative CT Scans

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